Dominion Push

[Agema]

If you've bottled an enemy up in a fortress (often their capital), and it's full to the brim with enemy units and mages such as to make an assault massively punishing, a Domkill may be the quickest and least painful option.

* * *

I don't really rate stealth preaching.

For most nations, a stealth preacher will be purchased instead of a mage. Fewer mages = less research and fewer battle mages. If you have a stealthy mage/priest (e.g. Vanheim, Eriu), most of the best things you could do with it involve magery, not stealthy preaching. I suppose once your research is finished, you could employ all your spare Vanjarls or whatever to ruin someone's Dom.

Offhand, you want to look for stealthy heretics to unpick Dom, maybe - Arco philosophers? MA Man has cheap castles, cheap temples and stealthy priests, so you could quickly devote a castle to pumping out Monks to ruin someone's Dom.

As a mass tactic, it's hard to see working very efficiently. It's got more usefulness just to target a few individual squares: highly productive ones to spoil an enemy's income, or ones you think you're going to fight on and want the morale/god/prophet bonuses on your side.

[LumenPlacidum]

EA Pangaea's most cost-effective researcher is the dryad, which is a stealthy, commander mage-priest with holy 2. They also have a splash of blood and the ability to blood sacrifice, with cheap temples. They get significant benefits from turmoil and can easily get along with sloth. Your good luck is someone else's bad luck. Seems like they have everything required to reap advantages from a weaponized dominion and to wield it pretty effectively.

[Redeyes]

The Marignons have extremely powerful blood sacrificing, with its ubiquitous holy 3 priests being capable of it. The might even have the strongest chassis for it, at least large scale.

I would be curious to see if it could be made into an effective offensive strategy, the problem as far as I can tell lies in the difficulty in directing the push in any given direction - you certainly can't save your allies from it or even focus on removing a single enemy from the game.